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TS 25.231 V0.3.0 (1999-06)Technical Specification

3rd Generation Partnership Project (3GPP);Technical Specification Group (TSG)

Radio Access Network (RAN);Working Group 1 (WG1);

Physical layer - Measurements

The present document has been developed within the 3 rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP. The

present document has not been subject to any approval process by the 3GPP

Organisational Partners and shall not be implemented.This Specification is provided for future development work within 3GPPonly. The Organisational Partners accept no liability for any use of this Specification.Specifications and reports for implementation of the 3GPPTM system should be obtained via the 3GPP Organisational Partners' Publications Offices.

Reference (.PDF)

Keywords

3GPP

Postal address

Office address

Internet

secretariat@3gpp.orgIndividual copies of this deliverable

can be downloaded from

http://www.3gpp.org

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Contents

Intellectual Property Rights......................................................................................................................5

Foreword..................................................................................................................................................51 Scope......................................................................................................................................................5

2 References..............................................................................................................................................5

3 Measurements in idle mode.....................................................................................................................63.1 Measurements for cell selection............................................................................................................................63.1.1 Cell selection monitoring frequency or cell set..................................................................................................63.1.2 Measurement from the cell selection monitoring set and reporting to higher layers........................................73.2 Measurements for cell reselection.........................................................................................................................73.2.1 Cell reselection monitoring frequency or cell set...............................................................................................73.2.1.1 Content of the cell reselection monitoring set for FDD cells.........................................................................73.2.1.2 Content of the cell reselection monitoring set for TDD cells.........................................................................73.2.1.3 Content of the cell reselection monitoring set for GSM cells.........................................................................73.2.2 Measurements for cell reselection and reporting to higher layers.....................................................................7

4 Measurements at call set-up...................................................................................................................74.1 Measurements for DCA....................................................................................................................................... ..84.1.1 Measurements reported from UE to the UTRAN..............................................................................................8

5 Measurements in connected mode...........................................................................................................85.1 Measurements for the handover preparation.........................................................................................................85.1.1 Cell sets for the handover preparation...............................................................................................................85.1.1.1 Overview of the different sets..........................................................................................................................85.1.1.2 Content of the sets...........................................................................................................................................95.1.1.2.1 handover monitoring set...............................................................................................................................95.1.1.2.1.1 FDD cells on the same frequency..............................................................................................................95.1.1.2.1.2 FDD cells on different frequencies............................................................................................................9

5.1.1.2.1.3 TDD cells 105.1.1.2.1.4 GSM cells 105.1.1.2.2 active set 105.1.1.2.3 candidate set...............................................................................................................................................105.1.2 Measurement triggering criteria.......................................................................................................................105.1.3 Measurements for the handover preparation from UTRA FDD at the UE.....................................................105.1.3.1 In general.......................................................................................................................................................105.1.3.2 Monitoring of FDD cells on the same frequency..........................................................................................115.1.3.3 Monitoring of cells on different frequencies (FDD, TDD and GSM)..........................................................115.1.3.3.1 Use of compressed mode/dual receiver for monitoring.............................................................................115.1.3.3.2 Parametrisation of the compressed mode ..................................................................................................115.1.3.3.3 Measurement requirements .......................................................................................................................125.1.3.3.4 Monitoring of FDD cells on other frequencies at the UE for the handover preparation from UTRA FDD

to UTRA FDD......................................................................................................................... .125.1.3.3.4.1 Setting of the compressed mode parameters...........................................................................................135.1.3.3.4.2 Measurements..........................................................................................................................................135.1.3.3.5 Monitoring of TDD cell at the UE for the handover preparation from UTRA FDD to UTRA TDD ......135.1.3.3.5.1 Setting of the compressed mode parameters...........................................................................................135.1.3.3.5.2 Measurements.........................................................................................................................................135.1.3.3.6 Measurements for the handover preparation from UTRA FDD to GSM at the UE.................................135.1.3.3.6.1 Introduction 135.1.3.3.6.2 Setting of compressed mode parameters for Power measurements........................................................145.1.3.3.6.3 Setting of compressed mode parameters for first SCH decoding without prior knowledge of timing

information ........................................................................................................................145.1.3.3.6.4 Setting of compressed mode parameters for first SCH decoding with prior timing information between

UTRAN serving cells and GSM target cells .....................................................................155.1.3.3.6.5 Setting of compressed mode parameters for SCH decoding for BSIC reconfirmation and procedure at

the UE.................................................................................................................................155.1.3.3.6.6 Parametrisation of the compressed mode for handover preparation to GSM............................ ......... ..165.1.3.4 Overall handover preparation at the UE.......................................................................................................16

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5.1.4 Mesurements for the Handover preparation in FDD at the UTRAN side.......................................................165.1.5 Measurements for the handover preparation from UTRA TDD at the UE.....................................................165.1.5.1 In general.......................................................................................................................................................165.1.5.2 Measurements for the handover preparation from UTRA TDD to UTRA TDD at the UE.........................165.1.5.2.1 In general 165.1.5.2.2 Monitoring of TDD cells ...........................................................................................................................165.1.5.2.2.1 Parametrisation/introduction of idle periods .........................................................................................165.1.5.2.2.2 Measurement requirements.....................................................................................................................175.1.5.3 Measurements for the handover preparation from UTRA TDD to UTRA FDD at the UE.........................175.1.5.4 Measurements for the handover preparation from UTRA TDD to GSM at the UE....................................175.1.5.4.1 Introduction................................................................................................................................................175.1.5.4.2 Monitoring GSM from TDD using idle TDD timeslots............................................................................175.1.5.4.2.1 Low data rate traffic using 1 uplink and 1 downlink slot.......................................................................175.1.5.4.2.2 Higher data rate trafic using more than 1 uplink and/or 1 downlink TDD timeslot.............................185.1.5.4.2.3 Use of TDD TSs release to accommodate monitoring windows............................................................205.1.5.4.3 Overall handover preparation at the UE....................................................................................................205.1.6 Mesurements for the Handover preparation in TDD at the UTRAN side.......................................................205.1.7 Measurement reporting to the higher layers in TDD..................................................................... ........ ........205.1.7.1 Reporting scheme..........................................................................................................................................205.1.7.2 Measurement report content for cells on the same frequency......................................................................20

5.1.7.2.1 Measurement report content for TDD cells ..............................................................................................215.1.7.2.2 Measurement report content for GSM cells...............................................................................................215.1.7.2.3 Measurement report content for DCA ......................................................................................................215.2 Measurements for the cell reselection in active mode........................................................................................215.3 measurements for power control ?.......................................................................................................................215.4 Measurements to support DCA when in connected mode with TDD................................................................215.4.1 Measurements by the UE.................................................................................................................................215.4.2 Measurements by the NodeB........................................................................................................................ ....215.5 Measurements on adjacent channels............................................................................................................. .....225.5.1.1 Frequencies to measure.................................................................................................................................225.5.1.2 Measurement to perform...............................................................................................................................225.6 Measurements for radio-link time-out (or sync loss) ?.......................................................................................22

6 Radio link measurements......................................................................................................................22

Annex 1 : Handover scenarios (Informative)...........................................................................................22Introduction...............................................................................................................................................................22UTRA-UTRA handover scenarios............................................................................................................................23UTRA-GSM handover scenarios..............................................................................................................................23

Annex 2 : Handover execution (Should be moved to S2.04 at some stage).............................................23Soft handover........................................................................................................................................................... .23

7 History.................................................................................................................................................25

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Intellectual Property Rights

Foreword

This Technical Specification (TS) has been produced by the 3G Partnership Project (3GPP) of the EuropeanTelecommunications Standards Institute (ETSI).

The contents of this TS are subject to change as the work continues

1 Scope

This 3GPP Telecommunication Specification TS contains the description of the measurements done at the UE andnetwork in order to support operation in idle mode and connected mode.

As far as the measurements in idle mode are concerned, this TS described the following :

measurements for the cell selection for a UE supporting FDD and/or TDD

measurements for cell reselection for a UE camping on an FDD or TDD cell

As far as the measurements in connected mode are concerned, this TS describes measurements when the UE isconnected to an FDD cell or cells (in Soft handover) or a TDD cell for the cell connected state (see reference [8]), orcamping on an FDD cell for the UTRA connected state. This TS provides the minimum requirements for the UE andnetworks. Some explanatory text is also contained in the TS but it is more of a descriptive nature than normative.

As far as the measurements for the handover preparation, this specification defines the requirements to the UE andUTRAN, as well as parametrisation rules for the compressed mode in order to accommodate idle periods. This latteraspects may need to be moved to some other specifications. The description of the compressed mode (different type ofcompressed frames define by the compressed mode A/B, the number if idle slots and the position of such transmissiongap) is outside the scope of this specification and is covered in [1] and [2].

2 References

The following documents contain provisions which, through reference in this text, constitute provisions of the presentdocument.

References are either specific (identified by date of publication, edition number, version number, etc.) ornon-specific.

For a specific reference, subsequent revisions do not apply.

For a non-specific reference, subsequent revisions do apply.

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3.1.2 Measurement from the cell selection monitoring set and reporting tohigher layers

3.2 Measurements for cell reselection

3.2.1 Cell reselection monitoring frequency or cell set

< WG1 note : this section should define how the frequencies or cells to measure for the cell reselection process arepassed to the physical layer of the UE by higher layers and what information is passed in terms of cell mode,frequency, synchronisation information, in form of scrambling codes. This set should be provided by the MAClayer in the primitive that triggers the measurement process. This is referred to as the priority list as far as the FDDand TDD cell/frequencies are concerned>.

From a very general descriptive point of view, when in idle mode, the UE continuously searches for new cells on thecurrent and other carrier frequencies. The measurement for the cell reselection are performed in basically the sameway as the cell selection. The main difference compared to the cell selection is that a UE has received a priority list

from the UTRAN, called the cell re-selection monitoring set, which provides information relative to the cells tomonitor.

As far as FDD cells are concerned, provision of the list significantly reduces the time and effort needed for thescrambling-code search (step 3) (see [4]). Also the complexity in the second step may be reduced if the priority listonly includes scrambling codes belonging to a subset of the total set of code groups. The priority list is continuouslyupdated to reflect the changing neighbourhood of the moving UE.

Content of the cell reselection monitoring set is further discussed in the following sections for FDD, TDD and GSMcells respectively.

3.2.1.1 Content of the cell reselection monitoring set for FDD cells

The content of the cell re-selection monitoring set as far as FDD cells are concerned provides the list of FDDcells/frequencies including the downlink scrambling codes and the order in which they should be searched for.

3.2.1.2 Content of the cell reselection monitoring set for TDD cells

The cell reselection monitoring set describes in which order to search for TDD cells.

3.2.1.3 Content of the cell reselection monitoring set for GSM cells

To be added

3.2.2 Measurements for cell reselection and reporting to higher layers

4 Measurements at call set-up

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4.1 Measurements for DCA

DCA is used to optimise the resource allocation by means of a channel quality criteria or traffic parameters. The DCAmeasurements are configured by the UTRAN.

The UE reports the measurements to the UTRAN. DCA measurements in the idle mode should be minimised.

4.1.1 Measurements reported from UE to the UTRAN

At call set-up the UE may on UTRAN request from the perform the interference on specified timeslots. Thosemeasurements performed at the physical layer are passed to higher layers and reported back to the UTRAN. Based onthese measurements the UTRAN selects appropriate resource units for the requested service.

5 Measurements in connected mode

5.1 Measurements for the handover preparation

5.1.1 Cell sets for the handover preparation

5.1.1.1 Overview of the different sets

The physical layer of the UE should be provided by higher layers the following lists of cells :

Handover Monitoring set: All cells (UTRA or from other systems like GSM) that the UE has been tasked by theUTRAN to monitor when in active mode.

Active Set: The UTRA cells currently assigning a downlink DPCH to the UE, which corresponds to the cellbetween which the UE in a soft handover with. The active set may only correspond to UTRA cells.

Handover candidate Set: The cells that are not currently in the Active Set but have been received by the UE withsufficient strength to indicate that the associated DPCHs could be successfully demodulated. These correspond tothe cells that are effectively reported by the UE to the UTRAN. These cells may be on the same or differentfrequencies from the current frequency assignment. Cells in the handover candidate set may be UTRA or GSMcells.

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higher layers as candidate cell may need to be measured more often than other cell, since they are among the xstrongest. >

5.1.1.2 Content of the sets

5.1.1.2.1 handover monitoring setThe handover monitoring set contains the cells to be monitored by the UE in connected mode. It is provided to the physical layer byhigher layers, as part of the primitives (see [8]). The handover monitoring set may contain cells on the same frequency and/orcells on different frequencies. The following sections indicate which information are included in the handover monitoring set forcell on the same frequency and cells on different frequencies.

5.1.1.2.1.1 FDD cells on the same frequency

For each cell to monitor at the same frequency, the handover monitoring list contains at least the followinginformation:

The cell scrambling code used for downlink scrambling.

The cell ID number

It is assumed that the mapping of the cell scrambling codes in relation to the synchronisation channel codes (groupsindicated by the secondary synchronisation channel) is known with the code grouping being determined beforehand.

Additionally there can be the following information on the UTRANs where timing information between cells is used:

The relative timing difference between the cell transmitting the handover monitoring list and each neighbouringcell on the same frequency.

The estimated accuracy of the timing difference indication.

This can be given for example in the following format:

Example of the timing information with 16 bits reserved for the message.

Code Measurement accuracy (step) Estimate of timing difference

00 Asynchronous (or 720ms) -

01 62.5s (symbol) 0 to 1.15x104 steps of 62.5s

10 625s (slot) 0 to 1.15x103 steps of 625s

11 10ms (frame) 0 to 7.2x102 steps of 10ms

5.1.1.2.1.2 FDD cells on different frequencies

For each cell to monitor at another frequency, the handover monitoring list contains at least the following information:

The cell scrambling code used for downlink scrambling.

The cell ID number

The carrier centre frequency of the cell

Additionally there can be the following information on the UTRANs where timing information between cells is used:

The relative timing difference between the cell transmitting the handover monitoring list and each neighbouringcell.

The estimated accuracy of the timing difference indication.

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5.1.1.2.1.3 TDD cells

The handover monitoring set contains for each TDD cell to monitor a frequency information and an information fieldCELL_PARAM for the cell parameters (toffset, long basic midamble code, short basic midamble code, scrambling code).

Each UE has stored a cell parameter list (see table below) for the TDD carrier which is common to the wholenetwork and which contains 128 sets of cell parameters.

Each set has a unique long basic midamble code, a unique short basic midamble code (optional) and a uniquescrambling code. Furthermore, each set has a toffset out of 32 different values.The information whether a long or a short basic midamble code is used for specific resources is configured by theUTRAN, e.g. BCH may be used.

CELL_PARAM Long basic midamble Short basic midamble Scrambling code toffset0 mPL0 (see mP in [5]) mPS0(see mP in [5]) Code 0 t01 MPL1 mPS1 Code 12 MPL2 mPS2 Code 2

3 MPL3 mPS3 Code 3

4 MPL4 mPS4 Code 4 t1

5 MPL5 mPS5 Code 56 MPL6 mPS6 Code 67 MPL7 mPS7 Code 7

.

.

.

124 mPL124 mPS124 Code 124 t31125 mPL125 mPS125 Code 125

126 mPL126 mPS126 Code 126127 mPL127 mPS127 Code 127

Table - :

Note: Similar timing information as for the FDD could be provided for TDD cells as well to aid the FDD-TDDhandover as TDD BCCH occurs only during two slots, thus measurements with timing information will be faster.

5.1.1.2.1.4 GSM cells

5.1.1.2.2 active set

5.1.1.2.3 candidate set

5.1.2 Measurement triggering criteria

5.1.3 Measurements for the handover preparation from UTRA FDD at theUE

5.1.3.1 In general

To be added

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5.1.3.2 Monitoring of FDD cells on the same frequency

During the measurement process of cells on the same frequencies, the UE shall find the necessary synchronisation tothe cells to measure using the primary and secondary synchronisation channels and also the knowledge of the possiblescrambling codes in use by the neighbouring cells.

As the UE does measurement, at least the following information is obtained:

The UE shall measure from the cells on the same frequency, belonging to the handover monitoring set, the Ec/I0 ofthe Primary CCPCH

Relative timing between the cells, measured for example from the phase difference between the scrambling code,depending on the timing difference between the cells.

5.1.3.3 Monitoring of cells on different frequencies (FDD, TDD and GSM)

5.1.3.3.1 Use of compressed mode/dual receiver for monitoring

A UE shall, on upper layers commands, monitor cells on other frequencies (FDD, TDD, GSM). To allow the UE toperform measurements, upper layers shall command that the UE enters in compressed mode, depending on the UEcapabilities.

In case of compressed mode decision, UTRAN shall communicate to the UE the parameters of the compressed mode,described in reference [2], 25.212.

A UE with a single receiver shall support downlink compressed mode.

Every UE shall support uplink compressed mode, when monitoring frequencies which are close to the uplinktransmission frequency (i.e. frequencies in the TDD or GSM 1800/1900 bands).

< WG1s note : the use of uplink compressed mode for single receiver UE when monitoring frequencies outside TDDand GSM 1800/1900 bands is for further study >

UE with dual receivers can perform independent measurements, with the use of a monitoring branch receiver, thatcan operate independently from the UTRA FDD receiver branch. Such UE do not need to support downlinkcompressed mode.

The following section provides rules to parametrise the compressed mode.

5.1.3.3.2 Parametrisation of the compressed mode

In response to a request from upper layers, the UTRAN shall signal to the UE the compressed mode parameters.

The following parameters characterize a transmission gap : TGL : Transmission Gap Length is the duration of no transmission, expressed in number of slots (e.g. used for

switching frequency, monitoring). SFN : The system frame number when the transmission gap starts

SN : The slot number when the transmission gap starts

With this definition, it is possible to have a flexible position of the transmission gap in the frame, as defined in [2].

The following parameters characterize a compressed mode pattern :

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TGP : Transmission Gap Period is the period of repetition of a set of consecutive frames containing up to 2transmission gaps (*).

TGL : As defined above TGD : Transmission Gap Distance is the duration of transmission between two consecutive transmission gaps

within a transmission gap period, expressed in number of frames. In case there is only one transmission gap in thetransmission gap period, this parameter shall be set to zero.

PD: Pattern duration is the total time of all TGPs expressed in number of frames. SFN : The system frame number when the first transmission gap starts

In a compressed mode pattern, the first transmission gap starts in the first frame of the pattern. The gaps have a fixedposition in the frames, and start in the slot position defined in [2].

(*) : Optionally, the set of parameters may contain 2 values TGP1 and TGP2, where TGP1 is used for the 1st and theconsecutive odd gap periods and TGP2 is used for the even ones. Note if TGP1=TGP2 this is equivalent to using onlyone TGP value.

In all cases, upper layers has control of individual UE parameters. The repetition of any pattern can be stopped onupper layers command.

TGL

TGD

TGP

PD

10 ms

Figure 1 : illustration of compressed mode pattern parameters

5.1.3.3.3 Measurement requirements

5.1.3.3.4 Monitoring of FDD cells on other frequencies at the UE for the handover preparationfrom UTRA FDD to UTRA FDD

Upper layers may ask FDD UE to perform preparation of inter-frequency handover to FDD. In such case, the UTRANsignals to the UE the handover monitoring set, and the if needed, the compressed mode parameters used to make theneeded measurements. Setting of the compressed mode parameters defined in section 7.1.3.3.2 for the preparation of

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handover from UTRA FDD to UTRA FDD is indicated in the following section. Measurements to be performed by thephysical layer is defined in section 7.1.1.3.3.4.2.

5.1.3.3.4.1 Setting of the compressed mode parameters

During the transmission gaps, the UE shall perform measurements so as to be able to report to the UTRAN the frame

timing, the scrambling code and the Ec/Io of Primary CCPCH of up to the [x] FDD cells in the handover monitoringset.

When compressed mode is used for cell acquisition at each target FDD frequency, the parameters of compressed modepattern are fixed to be :

TGL TGD TGP PD

5.1.3.3.4.2 Measurements

During the measurement process of FDD cells on a different frequency, the UE shall measure the followinginformation:

The UE shall measure from the FDD cells on another frequency, belonging to the handover monitoring set, theEc/I0 of the Primary CCPCH.

Relative timing between the scrambling codes of the serving and measured cell as derived from the scramblingcodes used on the Primary CCPCH.

5.1.3.3.5 Monitoring of TDD cell at the UE for the handover preparation from UTRA FDD toUTRA TDD

This section should describes particular rules to set the compressed mode parameters when monitoring TDD cell, bothfor the downlink and uplink compressed mode depending on the handover monitoring set, as well as provide somedescriptive text on the monitoring process itself.

5.1.3.3.5.1 Setting of the compressed mode parameters

5.1.3.3.5.2 Measurements

5.1.3.3.6 Measurements for the handover preparation from UTRA FDD to GSM at the UE

5.1.3.3.6.1 Introduction

Upper layers may ask dual mode FDD/GSM UE to perform preparation of inter-frequency handover to GSM. In suchcase, the UTRAN signals to the UE the handover monitoring set, and if needed, the compressed mode parameters usedto make the needed measurements.

The UE shall perform measurements so as to be able to report every [x msec] to the UTRAN the BSIC and the signalstrength of up to [y] GSM cells in the handover monitoring set.

The involved measurements are GSM BCCH power measurements (Section 7.1.3.3.6.3), initial GSM SCH or FCCHacquisition (Section 7.1.3.3.6.4), acquisition/tracking of GSM SCH or FCCH when timing information betweenUTRA serving cells and the target GSM cell is available (Section 7.1.3.3.6.5), and BSIC reconfirmation (Section

7.1.3.3.6.6).

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5.1.3.3.6.2 Setting of compressed mode parameters for Power measurements

When compressed mode is used for GSM BCCH power measurements, the parameters of compressed mode pattern arefixed to be :

TGL TGD TGP PD

In order to fulfill the expected GSM power measurements requirement, the UE can get effective measurementssamples during a time window of length Tmeas, equal to the transmission gap length reduced by an implementationmargin of [x], that includes the maximum allowed delay for a UEs synthetizer to switch from one FDD frequency toone GSM frequency and switch back to FDD frequency, plus some additional implementation margin.

5.1.3.3.6.3 Setting of compressed mode parameters for first SCH decoding withoutprior knowledge of timing information

The setting of the compressed mode parameters is described in this section when used for first SCH decoding of one

cell when there is no knowledge about the relative timing between the current FDD cells and the neighbouring GSMcell.

On upper layers command, UE shall pre-synchronise to the each of GSM cells in the handover monitoring set anddecode their BSIC. < Note : the proper reference to GSM specs should be added here >

When compressed mode is used to perform initial FCCH/SCH acquisition, the compressed mode pattern belongs to thelist of patterns in table .

In order to fulfill the expected GSM SCH speed requirement, the UE can get effective measurements samples during atime window of length Tmeas, equal to the transmission gap length reduced by an implementation margin of [x], thatincludes the maximum allowed delay for a UEs synthetizer to switch from one FDD frequency to one GSM frequencyand switch back to FDD frequency, plus some additional implementation margin.

TGL TGD TGP PD

Pattern 1 Tbd Tbd Tbd Tbd

Pattern 2 Tbd Tbd Tbd Tbd

Pattern 3 Tbd Tbd Tbd Tbd

Pattern 4 Tbd Tbd Tbd Tbd

Pattern 5 Tbd Tbd Tbd Tbd

Pattern 2N Tbd Tbd Tbd Tbd

Table .- List of compressed mode patterns used for initial GSM FCCH/SCH acquisition without timing information

Each pattern corresponds to a different compromise between speed of GSM SCH search and rate of use of compressedframes. On upper layers command, the repetition of the selected pattern can be stopped and/or replaced by one of theother listed patterns. Upper layers may also decide to alternate the use of different patterns periods.

Depending on the UEs capabilities, the search procedure may be sequential (tracking of FCCH burst before decodingof the first SCH) or parallel (parallel tracking of FCCH and SCH bursts). The latter solution achieves SCH decodingfaster than the first one, thus decreasing the needed number of repeated patterns.

Once the UE has completed the search it signals the UTRAN with the timing of the associated SCH burst or with

SCH-not-found (see < Editors note : reference to be inserted here >).

Whenever UE receives a new neighbour cell with a sufficiently high power level (see < Editors note : reference to beinserted here >), it shall perform a new SCH search procedure.

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When a compressed mode pattern is available, then it is up to the UE to trigger this search procedure with theavailable transmission gaps. In this case, no specific signalling is needed between the UE and the UTRAN.

When a compressed mode pattern is not available, the UE shall initiate the search procedure by sending a "requestnew cell search" message to the UTRAN. Based on the UEs capabilities for serial or parallel search as describedabove, the UTRAN then determines a suitable compressed mode pattern and signals this to the UE. The upper layerscan delay the onset of this pattern depending on the timing priority the Network Operator has set for new BSICidentification.

5.1.3.3.6.4 Setting of compressed mode parameters for first SCH decoding withprior timing information between UTRAN serving cells and GSM targetcells

UTRAN or UE may have some prior knowledge of timing difference between some FDD cells in UEs active set andsome GSM cells in the handover monitoring set. When this information is acquired by the UE (e.g. after initialFCCH/SCH detection) and on upper layers command, the UE shall report it to the upper layers for verification ofUTRANs information, and feedback of this information from UTRAN to the other UE.

When UTRAN or UE have this prior timing information, the compressed mode shall be scheduled by upper layerswith the intention that SCH (or FCCH if needed) on a specific GSM band can be decoded at the UE during thetransmission gap.

In such case, a transmission gap is scheduled once over 306 frames, equal to 13 GSM 51 multi-frame duration. Asthe UTRA 720 ms superframe shifts of superframe during the period, the 4 times 306 period can be used to fullyalign the timings of a UTRA FDD and a GSM cells.

The transmission gap parameters used for GSM FCCH/SCH tracking with prior timing information are :

TGL SFN SN

In addition to normal compressed mode parameters, UTRAN signals the following information to the UE :

The frame number where compressed mode occurs (frame number x+n times 306, where n=0,1,2,3)

The GSM carrier for which the particular compressed frame is intended (BS ID, carrier no, etc.)

Once the UE has completed the search, it signals the UTRAN with the timing of the associated SCH burst or withSCH-not-found and the UTRAN ceases the compressed mode pattern.

5.1.3.3.6.5 Setting of compressed mode parameters for SCH decoding for BSICreconfirmation and procedure at the UE

In this paragraph it is assumed that the UE has successfully decoded one SCH burst of a given neighbouring GSM cellduring the call.

When a compressed mode pattern is available, then it is up to the UE to trigger and perform the BSIC reconfirmationprocedure with the available transmission gaps. In this case, no specific signalling is needed between the UE and theUTRAN for BSIC reconfirmation procedure.

When no compressed mode pattern is available then it is up to the UE to trigger and perform the BSIC reconfirmationprocedure. In that case, UE indicates to the upper layers the schedule of the SCH burst of that cell, and the size of thenecessary transmission gap necessary to capture one SCH burst. The Network Operator decides the target time forBSIC reconfirmation and the upper layers uses this and the schedule indicated by the UE to determine the appropriatecompressed mode parameters.

Depending on whether UTRAN has an a priori timing knowledge of neighbouring GSM cells, the compressed mode

parameters shall be one of those described in section 7.1.3.3.6.3, or in section 7.1.3.3.6.4.

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5.1.3.3.6.6 Parametrisation of the compressed mode for handover preparation toGSM

Whereas section 7.1.3.3.6.3 described the compressed mode parametrisation for the initial synchronisation tracking orreconfirmation for one cell and the compressed mode parameters for power measurement for one of multiple cells,there is a need to define the global compressed mode parameters when considering the monitoring of all GSM cells.

5.1.3.4 Overall handover preparation at the UE

This section should explain how the inter-frequency handover preparation from UTRA FDD to UTRA (either FDD orTDD) and from UTRA to GSM are co-ordinated in terms of measurement and reporting at the UE. Whereas Section7.1.3.3.4, 7.1.3.3.5, and 7.1.3.3.6 give some principle for the monitoring of a given cell type and requirement in e.g.the dimensioning of the slotted mode, this section provides the overall requirement and measurement procedure.

5.1.4 Mesurements for the Handover preparation in FDD at the UTRANside

5.1.5 Measurements for the handover preparation from UTRA TDD at theUE

5.1.5.1 In general

5.1.5.2 Measurements for the handover preparation from UTRA TDD to UTRA TDDat the UE

5.1.5.2.1 In general

For the preparation of a handover from TDD to TDD the UE measures in its idle timeslots the received strength ofother cells. A mechanism that introduces idle timeslots on demand is for further study.For the search for other cells the UE is provided by a handover monitoring set by the UTRAN.

5.1.5.2.2 Monitoring of TDD cells

During the measurement process the UE shall find synchronisation to the cells to measure using the synchronizationchannel with the primary and the secondary synchronization code as well as the information contained in the cellparameter list.

The following information is obtained by the UE either from measuring the synchronisation channel or the CCPCH:

- signal strength of the measured cell

- relative timing between the cells, measured from the timing of the primary synchronisation code

5.1.5.2.2.1 Parametrisation/introduction of idle periods

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5.1.5.2.2.2 Measurement requirements

5.1.5.3 Measurements for the handover preparation from UTRA TDD to UTRA FDDat the UE

5.1.5.4 Measurements for the handover preparation from UTRA TDD to GSM at theUE

5.1.5.4.1 Introduction

UTRA/TDD-GSM dual mode terminals can be implemented without simultaneous use of two receiver chains.Although the frame length is different from GSM frame length, the GSM traffic channel and UTRA TDD channels

rely on similar 120 ms multi-frame structure.

A UE can do the measurements by efficiently using idle slots (Slot left idle between Tx and Rx and/or Rx and TX as aresult of the resource allocationOther alternatives, e. g. dual receiver, are for further study. Basic requirements tocorrectly perform a handover in GSM are described in GSM 05.08 Radio subsystem link control.

5.1.5.4.2 Monitoring GSM from TDD using idle TDD timeslots

Two kinds of UE should be distinguished: A single synthesiser UE has to switch in its idle periods from the TDDfrequency to the considered GSM frequency, monitor GSM and switch back to TDD afterwards, that means two timesa synthesiser switching time has to be considered. A dual synthesiser UE avoids this synthesiser switching time andthe monitoring periods are equal to the idle periods.

For preparation of a handover from TDD to GSM there are two procedures possible

To detect at first the FCCH burst and then the SCH burst (following one GSM frame later)

or searching parallel for FCCH and SCH bursts.

5.1.5.4.2.1 Low data rate traffic using 1 uplink and 1 downlink slot

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Figure 2: possible idle periods in a 16 TS frame with two occupied TS.

A is defined as the number of idle slots between the Tx and Rx slots and B the number of idle slots between the Rxand Tx slots. It is clear that A+B=14 time slots.

In the scope of low cost terminals, a [0.8] ms period is supposed to be required to perform a frequency jump fromUMTS to GSM. As detailed in table 1, this will let free periods of A*0,625-1.6 ms and B*0,625-1.6 ms during which

the mobile station can monitor GSM. In this table, the UL traffic is assumed to occupy TS0, and the duration ofmonitoring periods are indicated for each possible location of the DL TS.

Table- evaluates the average synchronisation time and maximum synchronisation time, where the announcedsynchronisation time corresponds to the time needed to find the FCCH. The FCCH is supposed to be perfectly detectedmeaning that the FCCH is found if it is entirely present in the monitoring window. The FCCH being found the SCHlocation is unambiguously known from that point.

DL TSn

Numberof free

TS in A

Numberof free

TS in B

Monitoringperiod within

A (ms)

Monitoringperiod within

B (ms)

Synchronisation average

time (ms)

Maximumsynchronisatio

n time (ms)

1 0 14 Not Used 7,15 43 140

2 1 13 NU 6,525 48 187

3 2 12 NU 5,900 56 188

4 3 11 NU 5,275 63 188

5 4 10 0.9 4,65 68 189

6 5 9 1,525 4,025 75 233

7 6 8 2,15 3,4 74 189

8 7 7 2,775 2,775 48 189

9 8 6 3,4 2,15 73 189

10 9 5 4,025 1,525 73 235

11 10 4 4,65 0.9 66 186

12 11 3 5,275 NU 61 186

13 12 2 5,900 NU 54 186

14 13 1 6,525 NU 47 186

15 14 0 7,15 NU 43 139

Table: example-monitoring periods and associated synchronisation time in a 16 TS frame with two busy TS andwith 0.8 ms switching time (*).

(*) All simulations have been performed with a random initial delay between GSM frames and UMTS frames

Each configuration of TS allocation described above allows a monitoring period sufficient to acquire synchronisation.

5.1.5.4.2.2 Higher data rate trafic using more than 1 uplink and/or 1 downlink TDDtimeslot

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The minimum idle time to detect a complete FCCH burst for all possible alignments between the GSM and the TDDframe structure (called guaranteed FCCH detection), assuming that monitoring happens every TDD frame, can becalculated as follows (tFCCH = one GSM slot):

(e.g for tsynth =0ms: 3 TDD consecutive idle timeslots needed, for tsynth =0,3ms: 4 slots, for tsynth =0,5ms: 4 slots, for tsynth=0,8ms: 5 slots). Under this conditions the FCCH detection time can never exceed the time of 660ms.

(For a more general consideration tsynth may be considered as a sum of all delays before starting monitoring ispossible.)

For detecting SCH instead of FCCH (for a parallel search) the same equation applies.

In the equation before the dual synthesiser UE is included if the synthesiser switching time is 0ms.

occupied slots=

16-idle slots

cases FCCH detection time in ms

Average maximum

2 120 37 189

3 560 46 328

4 1820 56 419

5 4368 70 568

6 8008 87 659

7 11440 110 660

8 12870 138 660

9 11440 169 660

10 8008 195 660

11 4368 215 660

12 1820 227 660

13 560 229 660

14 120 - -

15 16 - -

Table : FCCH detection time for a dual synthesizer UE monitoring GSM from TDD every TDD frame

In table for a given number of occupied slots in the TDD mode all possible cases of distributions of these occupiedTDD slots are considered (see cases). For every case arbitrary alignments of the TDD and the GSM frame structureare taken into account for calculating the average FCCH detection time (only these cases are used which guaranteeFCCH detection for all alignments; only the non-parallel FCCH search is reflected by the detection times in the table2).

The term occupied slots means that the UE is not able to monitor in these TDD slots.

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ms35213

ms102min +=++= synthFCCHsynthed, guarante tttt

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For a synthesiser switching time of one or one half TDD timeslot the number of needed consecutive idle TDDtimeslots is summarized in the table .

One-way switching timefor the synthesiser

Number of free consecutive TDDtimeslots needed in the frame for aguaranteed FCCH detection

1 TS (= 625s) 5

0.5 TS (=312s) 4

0 (dual synthesiser) 3

Table: link between the synthesiser performance and the number of free consecutive TSs for guaranteed FCCHdetection , needed for GSM monitoring

5.1.5.4.2.3 Use of TDD TSs release to accommodate monitoring windows

In high data-rate, when it is not possible to free the number of TS needed for an effective monitoring to prepare ahandover from UMTS to GSM, the data rate can be slightly reduced for the duration of the monitoring. This should beacceptable as in any case, the data rate needs to be adapted to the available resource in GSM before the handover canbe performed.

5.1.5.4.3 Overall handover preparation at the UE

This section should explain how the inter-frequency handover preparation from UTRA TDD to UTRA (either FDD or

TDD) and from UTRA to GSM are co-ordinated in terms of measurement and reporting at the UE. This sectionprovides the overall requirement and measurement procedure.

5.1.6 Mesurements for the Handover preparation in TDD at the UTRANside

5.1.7 Measurement reporting to the higher layers in TDD

5.1.7.1 Reporting scheme

The UE sends regular (or event driven) measurement reports to the UTRAN. The level of filtering done by thephysical layer vs. the filtering done by higher layers needs to be further discussed.

5.1.7.2 Measurement report content for cells on the same frequency

These measurements include (for cells on the same frequency)

The Cell ID

The relative signal strength

The relative timing information, accuracy TBD.

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Measurement report content for FDD cells on different frequencies

5.1.7.2.1 Measurement report content for TDD cells

5.1.7.2.2 Measurement report content for GSM cells

5.1.7.2.3 Measurement report content for DCA

Pathloss of a sub-set of cells ([7]bit quantisation; max. number of cells is [30]) Inter-cell interference measurements of all DL time slots requested by the UTRAN ([5] bit quantisation) BER of serving link before channel decoding ([4] bit quantisation) Transmission power of the UE on serving link ([6] bits quantisation) DTX flag indicating, whether measurements have been performed during DTX periods

5.2 Measurements for the cell reselection in active mode

When in active mode, the UE continuously searches for new base stations on the current carrier frequency. This cellsearch is carried out in basically the same way as the idle mode cell search.

5.3 measurements for power control ?

5.4 Measurements to support DCA when in connected mode withTDD

5.4.1 Measurements by the UE

While in active mode the DCA needs measurements for the reshuffling procedure (intra-cell handover). The followingmeasurements have to be performed bytheUE:

Pathloss of a set of cells provided by the UTRAN

Inter-cell interference measurements of downlink time slots (also on different frequencies) according to a listprovided by the UTRAN. Estimation of BER of serving link before channel decoding

5.4.2 Measurements by the NodeB

The following measurements have to be performed by the nodeB in order to support DCA:

Inter-cell interference measurements of uplink time slots (also on different frequencies) according to a list providedby the UTRAN ([5] bit quantisation).

Estimation of BER of serving link before channel decoding ([4] bit quantisation)

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5.5 Measurements on adjacent channels

5.5.1.1 Frequencies to measureOn the BCCH, UTRAN transmits frequency information of candidate frequencies and neighbouring frequencies. A

candidate frequency is defined as a frequency that can be used by the own network, and a neighbouring frequency is

defined as a frequency that is adjacent to a candidate frequency. Candidate frequencies are classified into adjacent

frequencies and non-adjacent frequencies. An adjacent frequency is defined as a candidate frequency that is adjacent

to a neighbouring frequency, and a non-adjacent frequency is defined as a candidate frequency that is not adjacent to

a neighbouring frequency. A pair of dl-link and up-link non-adjacent frequencies may be allocated to all UE.

5.5.1.2 Measurement to perform

To support adjacent channel protection rule, an MS measures Q 1 and Q2 , where Q1 is the received power in dBm of

the downlink adjacent frequency, and Q2 is the received power in dBm of the downlink neighbouring frequency that

is adjacent to the downlink adjacent frequency.

5.6 Measurements for radio-link time-out (or sync loss) ?

6 Radio link measurements

RSSI : Received signal strength for useful part

ISSI : Interference signal strength

SIR: Signal to interference ratio

Relative signal strength (for Handover)

Relative timing difference between cells = for FDD this corresponds to the phase difference between the scramblingcodes

Annex 1 : Handover scenarios (Informative)

Introduction

This section studies the handover scenarios from the deployment point of view. It should in particular provide therules for setting the handover monitoring set (see section ), in particular the number of GSM, FDD and TDD cells to

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monitor. Based on deployment scenarios and UEs speed, it should also set the requirement in terms of detection timeand reporting time of a strong cell.

As far as the handover between UTRA and GSM, the handover scenario will be based on interoperability aspectsdescribed in XX.16, which among other things will indicate when a handover is needed between UTRA and GSMfrom the service availability point of view.

UTRA-UTRA handover scenarios

UTRA-GSM handover scenarios

Annex 2 : Handover execution (Should be moved toS2.04 at some stage)

Soft handover

The serving cell (s) (the cells in the active set) are expected to have knowledge of the service used by the UE. The newcell decided to be added to the active set shall be informed that a new connection is desired, and it needs to have thefollowing minimum information forwarded to it via UTRAN.

Maximum data rate of the connection and other service parameters, such as coding schemes, number of parallelcode channels etc. parameters which form the set of parameters describing the different transport channelconfigurations in use both uplink and downlink.

The UE ID and uplink scrambling code

The relative timing information of the new cell, in respect to the timing UE is experiencing from the existingconnections (as measured by the UE at its location). Based on this the new cellcan determine what should be thetiming of the transmission initiated in respect to the timing of the common channels (BCCH) of the new cell.

As a response the UE needs to know via the existing connections:

From which frame (assuming active set update accepted) does the new cell initiate the transmission to the UE

What channelisation code(s) are used for that transmission. The channelisation codes from different cells are not

required to be the same as they are under different scrambling code anyway. The relative timing information, which needs to be made available at the new cell is indicated in Figure 1 (shows

the case where the two involved cells are managed by different Node Bs).

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PCCCHframe

PDCH/PCCHframe

MeasureToffset

Handovercommandand Toffset

UTRAN

Transmisionchanneland Toffset

BS Bchannelinformation

BS ABS B

Toffset

Figure 3. Making transmissions capable to be combined in the Rake receiver from timing point of view.

At the start of diversity handover, the reverse link dedicated physical channel transmitted by the MS, and theforward link dedicated physical channel transmitted by the diversity handover source BTS will have their radioframe number and scrambling code phase counted up continuously as usual, and they will not change at all.Naturally, the continuity of the user information mounted on them will also be guaranteed, and will not cause anyinterruption.

The synchronization timing upon starting diversity handover are presented in Fig. 3.2.5-4. The synchronisationestablishment flow upon intra/inter-cell diversity handover is described in Fig. 3.2.6-4.

(a)The MS measures the frame time difference of the radio frame at the same frame number between the reverselink dedicated physical channel and the perch channel transmitted at the handover destination BTS. Thesemeasurements shall be notified to the network. The measured value is the time difference of the frame timingof the reverse link dedicated physical channel against the frame timing of the perch channel. The values shallalways be positive values in chip units, and the range shall be 0 reverse link scrambling code cycle-1chip.

(b)The MS notifies the frame time difference measurement values as layer 3 signals to the BSC via the diversityhandover source BTS with the DCH of the reverse link dedicated physical channel.

(c) The BSC notifies the frame time difference measurement result, together with the frame offset and slot offsetset up upon originating/ terminating call connection, to the diversity handover destination BTS with layer 3signals. Furthermore, the BSC notifies radio parameters such as the spreading codes used at the handover

destination BTS etc., to the MS via the handover source BTS.(d) The MS starts the chip synchronisation establishment process of forward link channel from the handover

destination BTS with the notified radio parameters. The reverse link channels being transmitted shall continuetransmission without any operations performed.

(e)The handover destination BTS receives the notification of the above frame time difference frame offset, andslot offset. Utilising these informations, the BTS starts the transmission of forward link dedicated physicalchannels and starts the synchronization establishment process of reverse link dedicated physical channeltransmitted by the MS. See chapter 3.2.5.1 for the specific transmission timing of forward link dedicatedphysical channels, and the reception timing of reverse link dedicated physical channel. As soon as chipsynchronisation and frame synchronisation using Frame Synchronization Word are established, hard wiredtransmission shall be started.

(f) Based on the handover destination perch channel reception timing, the MS establishes chip synchronisation offorward link channel from handover destination BTS. As soon as chip synchronisation is established, maximalratio combining with the forward link channel from handover source BTS shall be started.

(See also Appendix D)

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Fig. 4 Synchronisation Establishment Flow Upon Intra/Inter-cell Diversity Handover

7 History

V0.2.0 22.04.99 First version created based on S2.31 version 2.0.0 at TSG-RAN#3 to reflect thenew specification numbering scheme and the status of the document

V0.3.0 04.06.99 The proposed changes contained in R1-99642 were agreed at the RANWG1#5.They were incorporated into this version 0.3.0, which corresponds henceto an agreed version by RAN WG1.

V0.3.0 22.06.99 Noted by TSG-RAN

The editor for TS 25.231 (Physical layer measurements) is

Evelyne Le StratNortel NetworksTel : +33 1 39 44 53 39, Fax : +33 1 39 44 50 12, e-mail: elestrat@nortelnetworks.com

This document is written in Microsoft Word 97.

TS 25.231 V0.3.0 (1999-06)

MS diversity handoversou

e BTS

diversithandover destinationBTS

Frame time differencemeasurement

Start forward link chip sync.establishment process Start forward link normal transmission

Send transmission information (whenthere is transmission info.)

Stop transmission of symbol for transportchannel (when there is no transmissioninformation)

Forward link chip synchronizationestablished

Start maximal ratio combining

Start reverse link chip synchronizationestablishment process

Reverse link chip synchronizationestablished

Frame synchronization judgement(Frame Synchronization Word detectedor CRC OK detected)

Reverse link synchronization established

Start hard wired transmssion of reverse link received information

during communication

Forward link transmission

Reverse linktransmission

FRAME TIME DIFFERENCEMEASUREMENT VALUE

layer 3 signal